You are Gordon Freeman, a scientist working at a top secret government laboratory.
Your team is working on discovering the implications of the Chaos Theory, but so far the results have been inconclusive.
However, you have the feeling that today’s experiment may provide answers one way or another…

This really felt more like a map pack than a mod. Every map just felt like some kind of arena like environment. The mapping was detailed in some spots but was mainly just really bland. The creator could have added a story. The title really has nothing to do with the mod. It might as well have been called 5 bland arenas. Anyways, pros and cons:
Pros:
some pretty good mapping detail in some spots in the mod
proper difficulty ramp up
clean running with no crashes
mostly fair gameplay
clever mentioning of the mod's title at the end
Cons:
no story
bland maps
a little over the top fight with the apache at the end of the mod
Overall, Chaos Theory gets a 7/10.
BTW, I also encountered a moment where I had to noclip because I had killed the apache and got a keycard and couldn't find its slot. That was also a little problem for me.

This really has nothing to do with Choas Theory, but teleportation again which takes you through 5 very different maps, each of them equally bland.
The name of the mod suggests a story, but there isn’t one apart from a vague notion Choas Theory which is merely a reason to have things go wrong and teleport you around different maps.
One of the maps where you vs against 4 Gargantua’s is dead easy because they come at one at a time… and have almost no health dieing from 2 double barrel shotgun blasts.
This part could have been good if they all came at you at once… or had more health.. or both.
What challenge there could have been was erased from all but the first map with playing a little chasing game with Gargantua and last one with the helicopter.

What story there could have been was wasted, Instead this is just a random map pack with a lack of details.